Im not dual booting nor triple booting. CentOS is the only OS on the system. I have have to format and reload. I just select the partitions re-name them back to / or /boot etc..and select to format with ext3 patition type. I dont actually select each partition and delete them then re-create them. I have always done this even in centos3 and I never had the problem in centos3. Matter of fact I installed a true RHEL4 install and it does the same thing, also same result of RHEL3 as in centos3.